Bill Miller:
I'm looking for a replacement oil temp gauge (100-240 limits but with a margin on both ends) that will show me progress in warming up, starting from say 30 or 50 degrees. The installed gauge on this 391B is pegged to the left at 100, so there is no trend info during warm up before takeoff. Anybody know the original specs for this range for the 391B? Or what replacement, with a wider scale would not require FAA approval? Also, what do you use for oil level range on preflight for the GO-435 ? My 1957 POH is a little sparse in this area.

I installed a set of Electronics International gauges because EI's MVP-50P engine monitor was still pending the set of individual instruments cost almost as much. Most were dual function temp and press.

click on http://www.aircraftspruce.com/catalog/inpages/ei-digitalgraphic2.php

This is a full size pic of the 2 1/4" instrument it is both temp and pressure. Actually I see it shows up here a little over sized as 2 3/4".

The moniter below is 6" if I remember correctly

I believe Gordon Cragg is a dealer for EI and can actually get EI instruments cheaper than Aircraft Spruce.